Core retainer having curved gates



NOV. 15, 1966 J. E SANDERS ET AL 3,285,354

CORE RETAINER HAVING CURVED GATES NOV 15, 1966 J. E. SANDERS ET AL CORE RETAINER HAVING CURVED GATES f5 Sheets-Sheet 2 Filed Dec. 26. 1965 Nov. 15, 1966 J, E. SANDERS ET AL 3,285,354

CORE RETAINER HAVING CURVED GATES United States Patent O 3,285 354 CORE RETAINER HAVING CURVED GATES John E. Sanders, West Haven, Adrian A. Disco, New Haven, and Anthony L. Massini and Donald Johnson, North Haven, Conn., assignors, by mesne assignments, to the United States of America as represented by the Secretary of the Navy Filed Dec. 26, 1963, Ser. No. 333,775 Claims. (Cl. 175-242) This invention relates to -the collection of sediment. More particularly, this invention relates to a core retainer having curved gates for the retention of sediment from the ocean bottom.

The problem of collecting core samples of rmly packed sand under water involves two special difficulties viz. penetration and retention. If a tube is driven into the sand by a steady or by a series of repeated Iblows in the same direction without intervening relief, the packing pressure between grains, owin-g to the incompressibility of the individual grains, is increased. Increased packing pressure ultimately causes refusal of further penetration of the tubes into the sand. As for retention, sand grains and their interstitial water behave as a fluid and tend to drain out of the sampling tube. Without a suitable core retainer, loss generally occurs as the hydrostatic pressure at the lower end of the tube increases from the weight of the ever lengthening column of sample and the weight of the water when the tube is raised above the water level to the deck of the ship.

We have invented a core retainer having curved gates, which eliminates sample loss in all -grades of sand, while the up-and-down directional vibration of the sampling tube eliminates the build up of packing pressure.

It is an object of this invention to provide a device for use in oceanographic research for the penetration of ocean bottom sediment by a sample tube.

Another object is to provide a device for use on a sampling tube for the retention of ocean bottom samples obtained by up and down vibrational underwater sampling procedures.

A further object is to provide a device in the form of a core retainer for a sampling tube of low fabrication and maintenance cost, high durability and facile in use under a wide variety of service conditions.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same become better understood by reference to the following detailed description when considered in connection with the accompanying drawing, wherein:

FIG. 1 is aview in section of the device in the open position ready for use.

FIG. 2 is a view taken on line 2--2 of FIG. l.

FIG. 3 is a view in section of the device in the closed position, thereby retaining -a sample in the tube.

FIG. 4 is a view taken on line 4 4 of FIG. 3.

Similar numerals refer -to similar parts throughout the several views.

As `shown in FIG. 1, the core retainer is provided with a cylindrical body 11 of open end construction in the form of a mounting and attachment housing. The function of the body is to join the entire assembly to the lower end of a sampling tube 12. The cylindrical body may also be provided with an inner shoulder 13 for use as a supporting platform for the plastic core liner 14 that usually lits Within the steel sample tube.

The upper portion of the cylindrical body is provided with a thread bearing end 15 which is attached with the lower thread bearin-g end 16 of an attachment collar. The latter element` secures the body of the core retainer in position by abutment with the outwardly projecting of the gate.

ice

shoulder 17 on the wall of the sampling barrel. The lower portion of the body of the core retainer is also provided with a :thread Ibearing end 18 for mating attachment with the upper thread bearing end 19 of the cutting head. The latter head is beveled both exteriorly and interiorly in order to facilitate penetration when in use. The head is also provided with a small circular shoulder 21 which limits the downward movement of the external sliding sleeve 22.

The wall of the lower por-tion of the body of the core retainer is of enlarged cross-section to facilitate the provision of two diametrically opposed openings 23 and 24, each of which is adapted to accommodate the passage of a lever. Each of the levers 25 and 26 extend between the external sliding sleeve 22 and the internal curved gates 27 and 28. One of the levers 25, which is secured to the sliding sleeve 22 by a pivot pin 29, passes through an opening 23 and is secured to an arm 31 of the curved gate 27 by another pivot pin 32. The second lever 26, which is also secured to the slidin-g sleeve 22 'by a pivot pin 34, passes through the second opening 24 and is secured to the arm 35 of the second curved gate 28 by another pin 36. These two levers 25 and 26 transmit movement from the sliding sleeve 22 to the gates 27 and 28.v

The external sliding sleeve 22 opens and closes the interval curved gates 27 and 28 by its upward and downward movement. A projecting pin 37 accommodates a groove in the external sleeve 22 to prevent rotation of the sleeve, since rotation would bind the levers 25 and 26 and inhibit their easy action. The upward movement of the sleeve 22 is limited by the raised circular ledge 38 on the outer wall of the body 11 of the core retainer, while the downward movement is limited by the raised circular ledge 21 on the cutting head. The raised circular ledge 38 or stop permit the external sleeve 22 and walls of the body 11 of the core retainer to absorb the stresses which arise during penetration and extraction. These stops also prevent such stresses from being transferred by the sleeve to the connecting levers 25 and 26 or to the internally curved gates 27 and 28. The lower edge 3-9 of the external sliding sleeve is beveled so that the -beveled edge functions as a plow and dislodges any thin layer of sediment that may have adhered to the small recess space ahead of it. The upper edge 41 of the sliding sleeve should not be beveled; a greater width is needed to provide extra bearing area for the strength needed during penetration. As shown in FIG. l, the upper edge of the external sleeve is pressed firmly against the upper stop 38 during penetration so that no recessed space is available for the packing of sediment. As heretofore described, a connecting lever extends from the external sliding sleeve 22 to each of the arms 31 and 35 on each of the internally curved gates 27 and 28.

The tWo curved gates 27 land 28 are cut `from a cylinder whose inside ldiameter is the same as that of the liner tube inside the steel sampling tube. Thty are machined so that they form a tight junction when their ed'ges are in contact, and they must be shaped so that they completely lill the orifice of the sampling tube when closed. They are substantially in the shape of the center .portion of a semi-circular arc. Each gate resembles a vaulted arch las shown in FIG. 2. The inside wall of the body of the core retainer is recessed 43 to permit the gates to be countersunk. When properly mounted in their recessed housings, the gates do not interfere with entry of the sample, nor do they mark or scratch it in any Way. Each gate requires a small pivoting arm 31 and 35 which is atixed to the outside in line with the radius of curvature 'Ihis arm not only permits the gates to move toward each other :as they close but allows particles to ble in the light of the above teachings. be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

pass through rather than jam the gates open. The distinct advantage of the internal curved-gate core retainer is that the apparatus does not rely on functional drag against the sample to activate closing. The downward motion of the external sliding sleeve forces the curved gates together as shown in FIGS. 3 Iand 4.

When the apparatus 'above disclosed is driven into the sediment, the external sliding sleeve 22 moves to the position shown in FIG. 1 with its upper e-dge 41, abutting circular ledge 38 of the cylindrical body member 11. internal curved gates 27 and 28 are opened and the sediment sample enters the interior of core liner 14. When the apparatus is extracted from the sediment, the external sliding sleeve 22 is effectively displaced downwardly due to the greater resistance presented by its upper edge 41 to this withdrawal, and the curved gates move to the closed condition shown in FIG. 3, preventing any escape of the sample.

The

Obviously, many modifications and variations are possi- It is therefore to We claim: 1. A core lretainer comprising a cutting head having an upper end, a collar having a lower end, a hollow body having an upper and lower open end,

said upper end of sai-d body secured to said lower end of said collar and said lower end of said body secured to said upper end of said cutting head, said body having a lower end portion provided with two opposed openings, a pair of opposed curved gates pivotally secured to said lower end of body adjacent said openings, a sleeve slidably fitted around said body and over said openings, and a pair of elongated levers,

each of said levers passing through one of said openings land being pivotally secured to said sleeve and one of said separate curved gates, whereby said levers open and close said curved gates within said body in response to movement of said sleeve.

i 2. Arcore retainer comprising a pair of opposed curved gates each of which is pivot-` ally secured over one of said openings, each of said curved gates having a body in the form of a -center portion of a semi-circular arc,

ka. sleeve slidably fitted around said body and over saidopenings, and a pai-r of elongated levers each of which is provided with a first and second end,

said first end of each of said levers pivotally secured to said sleeve, and said second end of each of said levers extending through one of said openings in said body and pivotally secured to one of said curved gates, whereby said levers open and close said curved gates within said body, in response to movement of said 1eeve,

core retainer comprising: tt g 'head having an upper end,

aving a lower end,

a hollow body having an upper and lower open end,

said upper end of said body secured to said lower end of said collar'and said lower end of said body secured to said upper end of said cutting head, said body having a lower end portion provided with a irst and second diametrically opposed Opening, a first and second curved gate each of which is pivotally secured over one of said separate openings,

each of said curved gates having a body in the form of a center portion of a semi-circular arc, a sleeve slidably fitted a-round said body and over both of said openings, and a irst and second elongated lever,

said first lever passing through said irst opening and pivotally secured between said sleeve and said first curved gate, and said second lever passing through said second opening and pivotally secured between said sleeve and said second curved gate, whereby said levers open and close said curved lgates within said body in response to movement of said Isleeve on said body. 4. A core retainer Vcomprising a cutting head of open end construction having an upper thread bearing end, a collar of open end construction having a lower thread bearing end, a hollow body having an upper and lower thread bearing end intermediate said cutting head and said collar, said upper end of said body secured to said lower end of said collar and said lower end of said body secured to said upper end of said cutting head, said body having a lower end with two opposed openings, a pair of opposed curved gates pivotally secured to said lower end portion within said body and over said openings,

each of said curved gates having a body in the form of a central arc portion of a semi-circle, a sleeve slidably fitted around said body and over said openings, a pair of elongated levers each of which is provided with .a rst and second end,

said first end of each said levers pivotally secured to said sleeve, and said second end of each of said levers extending through one of said openings in said body and pivotally secured to one of said curved gates, whereby said levers open and close said curved gates within said body in response to movement of said sleeve,

said curved gates in the closed position forming a vaulted arc with each other within said body. 5. A core retainer comprising a cylindrical cutting head of open end construction having an upper thread bearing end, a cylindrical collar of open end construction having a lower thread bearing end, ya hollow cylindrical body intermediate said cutting head and said collar,

said body having an upper and lower thread bearing end and a lower end portion of enlarged cross section 'provided with a iirst and second diametrically opposed openings, a first and second curved gate pivotally secured to said lower end portion within said body,

portion provided each of said curved gates having a body in the form a sleeve slidably fitted around said body and over said.

openings,

a -rst and second elongated lever each of which is provided with an upper and lower end,

said lower end of said first lever pivotally secured to said rst curve gate 'and said upper end of said first lever extending through said rst opening in said body and pivot-ally secured to said sleeve, and said lower end of said secondlever `=pivotally secured to said second curve gate land said upper end of said second lever extending through said second opening in said body and pivotally secured to said sleeve, whereby said levers simultaneously open and close said curved gates Within said body responsive to the upward and downward movement of said sleeve on said body,

said iirst and second curved gates in the closed position forming a vaulted arc with each other within said body.

5 References Cited by the Examiner UNITED STATES PATENTS 18,500 6/1832 Stone 175-254 X 1,145,323 7/1915 Lindbeng 175--254 10 2,028,579 1/1936 Wright 175-254 3,039,547 6/ 1962 Glover 175-251 CHARLES E. OCONNELL, Primary Examinez'.

15 N. C. BYERS, Assistant Examiner. 

1. A CORE RETAINER COMPRISING A CUTTING HEAD HAVING AN UPPER END, A COLLAR HAVING A LOWER END, A HOLLOW BODY HAVING AN UPPER AND LOWER OPEN END, SAID UPPER END OF SAID BODY SECURED TO SAID LOWER END OF SAID COLLAR AND SAID LOWER END OF SAID BODY SECURED TO SAID UPPER END OF SAID CUTTING HEAD, SAID BODY HAVING A LOWER END PORTION PROVIDED WITH TWO OPPOSED OPENINGS, A PAIR OF OPPOSEED CURVED GATES PIVOTALLY SECURED TO SAID LOWER END OF BODY ADJACENT SAID OPENINGS, A SLEEVE SLIDABLY FITTED AROUND SAID BODY AND OVER SAID OPENINGS, AND A PAIR OF ELONGATED LEVERS, 